You exaggerated your guitar skills and a sim asks you to play at their wedding.

I chose keep up charade and made the offering sim upset. My playable sim was not affected. The offering sim was a non playable I had moved out of my home. The results of her being upset were interesting. If they are the same if one of our playable sims is offering (the one having the wedding), it could be problematic for a few hours.
First of all, the surprising choice came when my sim went to a party. So my moved out sim was at the party. She was crying all the time and showed up on choice lists but was grayed out.

If you tapped on her directly, or on her name on a list, a message said she was upset.

When I returned home, she wasn't around. She's moved out, but has stories with 2 active sims, so can usually be called to socialize or sometimes wanders through. When I tried to call her with either active sim who has a story with her, she would not come and I got a message she was upset. So it affected her interactions with all a sims, not just the sim who messed up her wedding.

You exaggerated your guitar skills and a sim asks you to play at their wedding.
Screenshot_2018-07-10-11-54-17-1.png
I chose keep up charade and made the offering sim upset. My playable sim was not affected. The offering sim was a non playable I had moved out of my home. The results of her being upset were interesting. If they are the same if one of our playable sims is offering (the one having the wedding), it could be problematic for a few hours.
First of all, the surprising choice came when my sim went to a party. So my moved out sim was at the party. She was crying all the time and showed up on choice lists but was grayed out.

If you tapped on her directly, or on her name on a list, a message said she was upset.
Screenshot_2018-07-10-11-55-22-1.png
Screenshot_2018-07-10-11-57-18-1.png
Screenshot_2018-07-10-11-56-31-1.png
When I returned home, she wasn't around. She's moved out, but has stories with 2 active sims, so can usually be called to socialize or sometimes wanders through. When I tried to call her with either active sim who has a story with her, she would not come and I got a message she was upset. So it affected her interactions with all a sims, not just the sim who messed up her wedding.
Screenshot_2018-07-10-12-18-16-1.png

Got this one again. This time with two playables. Sad sim Abra was weeping at party and work, but responded to all commands. When tried to socialize with another playable sim back home by tapping on her or her box in friends list, got the "Abra is upset" message.

Should your sim go to a friend's birthday party, even though sim doesn't like some of their friends? I chose "clean fridge" and got the vomit effects. No problem with getting sim to do anything, but visuals of the restaurant cook vomiting while at work made me worry for simtown's health.

Your sim is asked to buy something to help a struggling furniture store. I chose "buy online" No negative consequences. Looked up the other items afterwards (you can't while in surprising choice) and they are
Hearth Time fireplace, normally $275
Birdbath, normally $75
Large hand loomed rug, normally $25
By the way, the rug has no color options, only the red.

Sim is asked to help plan a party for work. I chose "be a flake" and let my sim cry. No effects on response to commands. Affected my other sims trying to socialize with her, but I rarely do that, so wasn't an issue for me. Might be if you wanted to do a social task between your sims.

And time for another rant....most surprising choices are starting to feel like extortion by Maxis...pay up simcash/cupcake or we'll harm your sim.

Your sim's friend tells them they don't like another friend. I chose the cheap option "I don't care" (The simcash option is SO unrealistically high! Does ANYONE really pay it?)

Your sim will be really rude, which I hate, and the other sim will cry for a while. But maybe they deserve it because they started it by dissing one of your sim's friends.

What's a bit odd is the choice was given when my sim arrived at a party and it brought the other sim along. The other sim was a sim who I'd moved out and never made playable. She was an aunt to my playable sim. This is the second time it happened. (Different non playable, different playable sim, different relationships each time.)